Question! Do you know the size of the tank? Sometimes LFS employees say you can fit goldfish in it, when you really can't. I'm not doubting it, but I'd help to know what size the tank is. =)
I have a Ryukin.. so I could probably help a bit on any specific questions.

And... don't count on being able to safely put fish in on this Friday. Tanks need some time to cycle.. this is a very important step.